# HER2-positive breast cancer

Source: https://onco.cc/cancers/breast-her2-positive/  
OnCo record `breast-her2-positive` (Cancer). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

HER2-positive breast cancer was once the most aggressive subtype and is now one of the most treatable, thanks to trastuzumab and, more recently, Enhertu.

## Summary

HER2-positive breast cancer (15-20% of cases; HER2 IHC 3+ or ISH-amplified) was the most aggressive subtype until trastuzumab (1998) made it one of the most treatable. The modern curative pathway is response-adapted: neoadjuvant chemotherapy with dual HER2 blockade (or, since 2026, T-DXd followed by THP), surgery, then either antibody completion for patients with a pathologic complete response or an ADC for residual disease (T-DM1 from KATHERINE, now T-DXd from DESTINY-Breast05). Small node-negative tumours are cured with paclitaxel-trastuzumab alone; PHERGain showed that an early PET response can spare a third of patients chemotherapy altogether. Extended adjuvant neratinib and adjuvant pertuzumab add small gains in higher-risk, node-positive disease.

Metastatic disease has been transformed twice: by CLEOPATRA's pertuzumab (OS 57 months) and then by trastuzumab deruxtecan, which beat T-DM1 by a wide margin in second line (DESTINY-Breast03) and beat THP in first line (DESTINY-Breast09, PFS 40.7 months; approved 2025). Brain metastases, which develop in up to half of patients, are now treatable systemically with tucatinib (HER2CLIMB) and T-DXd (DESTINY-Breast12). HER2CLIMB-05 (tucatinib maintenance) and PATINA (palbociclib maintenance in HR+/HER2+, approved 2026) intensify chemotherapy-free maintenance, and a wave of Chinese HER2 ADCs (trastuzumab rezetecan, BL-M07D1, ARX788, disitamab vedotin) is producing Enhertu-scale results.

Open problems are the sequencing of HER2 ADCs after T-DXd (payload cross-resistance), interstitial lung disease, cardiotoxicity across years of therapy, the cost and duration of antibody therapy, brain metastases prevention, and de-escalation: identifying the substantial fraction of patients who are over-treated. The pipeline is defined by T-DXd's move into every curative setting, tucatinib-based maintenance, next-generation and biparatopic HER2 ADCs (zanidatamab zovodotin), HER2 CAR-T and vaccines, and imaging- and ctDNA-adapted de-escalation trials.

## Fields

- Kind: Cancer
- Last checked: 2026-09-25
- Also known as: HER2 positive ER positive breast cancer; triple positive breast cancer; ER positive HER2 positive; HER2+ HR+; HER2-positive hormone receptor-positive; HER2 3+ breast cancer; HER2 amplified breast cancer
- Tags: breast; spike
- Group: breast
- Burden: 15-20% of breast cancers (roughly 400,000 cases per year worldwide). Ten-year survival for early-stage disease treated with trastuzumab-based therapy exceeds 80%.
- Subtypes: HER2-enriched (PAM50; highest pCR rates to HER2 blockade); HR+/HER2+ ('triple-positive', ~50% of HER2+; lower pCR, endocrine therapy and CDK4/6 maintenance relevant); HR-/HER2+ (higher pCR, more relapse in first 3 years); HER2-mutant (activating mutations without amplification; T-DXd tumour-agnostic, HER2 TKIs; more common in lobular and HER2-low); HER2 heterogeneous tumours (mixed amplified and non-amplified clones; lower pCR); Small node-negative (stage I) disease cured by de-escalated therapy
- Biomarkers: HER2 IHC 3+ or ISH-amplified; HR status; pCR after neoadjuvant therapy; HER2 IHC 3+ or IHC 2+ with ISH amplification (ASCO/CAP 2018 criteria); HER2 heterogeneity; HR status (drives triple-positive management, PATINA eligibility); Pathologic complete response after neoadjuvant therapy (selects T-DM1/T-DXd post-neoadjuvant); Early FDG-PET response (PHERGain de-escalation); LVEF by echocardiography or MUGA every 3 months on anti-HER2 therapy; Brain MRI when symptomatic; surveillance MRI debated; HER2 status on re-biopsy at progression (conversion in 10-15%); PIK3CA mutation (lower pCR; INAVO122 tests inavolisib in HER2+); ctDNA MRD (investigational for post-neoadjuvant escalation)

## Sections of this record

The page is a hub with ten sections in reading order; large sections have their own page. The same plan as JSON: https://onco.cc/api/v1/cancers/breast-her2-positive/sections.json

- Overview (on the hub): The TL;DR, the family this cancer belongs to, the organ, who gets it and what the state of the art is. https://onco.cc/cancers/breast-her2-positive/#overview [2 subtypes, 6 state-of-the-art points]
- Types and stages (on the hub): Anatomy, the subtypes and how they differ, how it is staged, and where advanced disease spreads. https://onco.cc/cancers/breast-her2-positive/#what-it-is [8 subtypes, 5 sites of spread]
- Symptoms and diagnosis (on the hub): How this cancer shows itself, how the diagnosis is confirmed, and the biomarkers clinicians test for. https://onco.cc/cancers/breast-her2-positive/#finding-it [12 biomarkers, 2 prevalence rows]
- Treatment (on the hub): The standard of care by setting, the medicines, surgery and radiotherapy named in it, and the regimens behind them. https://onco.cc/cancers/breast-her2-positive/#treating-it [10 settings, 10 regimens, 9 decisions with options]
- Trials and papers (own page): Trials recruiting now, the landmark trials, the trials held by this cancer's subtypes, the key papers and what they mean, the latest literature, and the milestones year by year. https://onco.cc/cancers/breast-her2-positive/evidence/ [120 trials, 20 key papers, 15 milestones]
- Biology and targets (on the hub): The molecular landscape: the targets and how often each appears, the pathways, the mechanics stages and the preclinical models. https://onco.cc/cancers/breast-her2-positive/#science [11 targets, 6 pathways, 5 preclinical models]
- Countries and centres (own page): Cases by country, the UK and NHS pathway and other country lenses, the expert centres with trials on record, and the centres named on this cancer's subtypes. https://onco.cc/cancers/breast-her2-positive/where-you-are/ [20 centres, 20 centres in the subtypes, 16 UK centres]
- Decisions and support (own page): The decisions you may face, the aids that walk through them, the warnings on record, the first sixty days and the questions to ask. https://onco.cc/cancers/breast-her2-positive/living-with-it/ [37 questions, 6 red cards]
- Pipeline and open problems (own page): Everything in development, the medicines held by this cancer's subtypes, the open problems and what is being done about them, the roadmaps, and what changed on this record. https://onco.cc/cancers/breast-her2-positive/coming/ [38 medicines, 2 medicines in the subtypes, 120 trials, 20 ideas, 8 open problems]
- Data (own page): Every connected record, the notes, the JSON, Markdown and RDF twins, and where the record came from and when it was checked. https://onco.cc/cancers/breast-her2-positive/data/ [447 connected records, 1 note]

## Standard of care

- Stage I (≤2-3 cm, node-negative): Surgery then weekly paclitaxel × 12 + trastuzumab × 1 year (APT); T-DM1 × 17 cycles is an alternative (ATEMPT). Endocrine therapy if HR+. ([APT (adjuvant paclitaxel-trastuzumab)](https://onco.cc/trials/apt-trial/), [Paclitaxel / nab-paclitaxel](https://onco.cc/drugs/paclitaxel/), [Trastuzumab](https://onco.cc/drugs/trastuzumab/), [Trastuzumab emtansine](https://onco.cc/drugs/trastuzumab-emtansine/))
- Stage II-III, neoadjuvant: TCHP (docetaxel, carboplatin, trastuzumab, pertuzumab) or anthracycline-taxane + HP; from 2026, T-DXd × 4 → THP (DESTINY-Breast11, pCR 67%). PET-adapted chemotherapy omission (PHERGain) in trials. ([DESTINY-Breast11](https://onco.cc/trials/destiny-breast11/), [Trastuzumab deruxtecan](https://onco.cc/drugs/trastuzumab-deruxtecan/), [Pertuzumab](https://onco.cc/drugs/pertuzumab/), [PHERGain](https://onco.cc/trials/phergain/))
- Post-neoadjuvant, pathologic complete response: Complete 1 year of trastuzumab (± pertuzumab if node-positive at diagnosis); endocrine therapy if HR+; radiation per stage. ([Trastuzumab](https://onco.cc/drugs/trastuzumab/), [Pertuzumab](https://onco.cc/drugs/pertuzumab/), [APHINITY](https://onco.cc/trials/aphinity/), [HERA, NSABP B-31 & NCCTG N9831 (adjuvant trastuzumab)](https://onco.cc/trials/hera-b31-n9831/))
- Post-neoadjuvant, residual invasive disease: T-DXd (DESTINY-Breast05, iDFS HR 0.47 vs T-DM1; approved 2026) replacing T-DM1 (KATHERINE); consider extended adjuvant neratinib for HR+ high-risk. ([DESTINY-Breast05](https://onco.cc/trials/destiny-breast05/), [KATHERINE](https://onco.cc/trials/katherine/), [Trastuzumab deruxtecan](https://onco.cc/drugs/trastuzumab-deruxtecan/), [Trastuzumab emtansine](https://onco.cc/drugs/trastuzumab-emtansine/), [Neratinib](https://onco.cc/drugs/neratinib/))
- Adjuvant (upfront surgery), node-positive: Chemotherapy + trastuzumab + pertuzumab for 1 year (APHINITY); trastuzumab alone for lower risk; 6 months acceptable where resources are limited (PERSEPHONE). ([APHINITY](https://onco.cc/trials/aphinity/), [PERSEPHONE](https://onco.cc/trials/persephone/), [Pertuzumab](https://onco.cc/drugs/pertuzumab/), [Trastuzumab](https://onco.cc/drugs/trastuzumab/))
- Metastatic, first line: T-DXd + pertuzumab (DESTINY-Breast09, PFS 40.7 months; approved 2025) or taxane + trastuzumab + pertuzumab (CLEOPATRA) followed by maintenance: HP ± tucatinib (HER2CLIMB-05) and, if HR+, endocrine therapy + palbociclib (PATINA, approved 2026). ([DESTINY-Breast09](https://onco.cc/trials/destiny-breast09/), [CLEOPATRA](https://onco.cc/trials/cleopatra/), [HER2CLIMB-05](https://onco.cc/trials/her2climb-05/), [Trastuzumab deruxtecan](https://onco.cc/drugs/trastuzumab-deruxtecan/), [Pertuzumab](https://onco.cc/drugs/pertuzumab/), [Tucatinib](https://onco.cc/drugs/tucatinib/), [Palbociclib](https://onco.cc/drugs/palbociclib/))
- Metastatic, second line: T-DXd if not used first line (DESTINY-Breast03, PFS HR 0.33 vs T-DM1); tucatinib + trastuzumab + capecitabine, especially with brain metastases (HER2CLIMB). ([DESTINY-Breast03](https://onco.cc/trials/destiny-breast03/), [HER2CLIMB](https://onco.cc/trials/her2climb/), [Trastuzumab deruxtecan](https://onco.cc/drugs/trastuzumab-deruxtecan/), [Tucatinib](https://onco.cc/drugs/tucatinib/))
- Metastatic, later lines: T-DM1; neratinib or lapatinib + capecitabine; margetuximab + chemotherapy; trastuzumab + chemotherapy (continued HER2 blockade); zanidatamab and Chinese ADCs (trastuzumab rezetecan, disitamab vedotin) where available; trials. ([Trastuzumab emtansine](https://onco.cc/drugs/trastuzumab-emtansine/), [Neratinib](https://onco.cc/drugs/neratinib/), [Lapatinib](https://onco.cc/drugs/lapatinib/), [Margetuximab](https://onco.cc/drugs/margetuximab/), [Zanidatamab](https://onco.cc/drugs/zanidatamab/), [Trastuzumab rezetecan](https://onco.cc/drugs/trastuzumab-rezetecan/), [Disitamab vedotin](https://onco.cc/drugs/disitamab-vedotin/))
- Brain metastases: Systemic: tucatinib triplet or T-DXd (DESTINY-Breast12, intracranial ORR 72%); local: stereotactic radiosurgery or surgery for symptomatic or large lesions; whole-brain RT reserved. ([HER2CLIMB](https://onco.cc/trials/her2climb/), [DESTINY-Breast12](https://onco.cc/trials/destiny-breast12/), [Tucatinib](https://onco.cc/drugs/tucatinib/), [Trastuzumab deruxtecan](https://onco.cc/drugs/trastuzumab-deruxtecan/), [SBRT / SABR (stereotactic radiotherapy)](https://onco.cc/technologies/sbrt/))
- Cardiac monitoring and survivorship: LVEF every 3 months during anti-HER2 therapy; hold and cardioprotect for declines; anthracycline-free regimens preferred; long-term surveillance for late recurrence in HR+/HER2+. ([Cardio-oncology](https://onco.cc/technologies/cardio-oncology/), [PERSEPHONE](https://onco.cc/trials/persephone/))

## State of the art

- Ten-year survival above 80% for early disease: the subtype with the poorest outlook in the 1990s is now one of the most treatable.
- Response-adapted curative therapy: pCR patients de-escalate, residual disease escalates to an ADC (now T-DXd, iDFS HR 0.47 vs T-DM1).
- T-DXd across the continuum: neoadjuvant (2026), post-neoadjuvant (2026), first-line metastatic with pertuzumab (2025, PFS 40.7 months), second line, and brain metastases.
- Systemic control of brain metastases (tucatinib, T-DXd) allowing deferral of radiation.
- Chemotherapy-free maintenance intensification: tucatinib (HER2CLIMB-05) and palbociclib for HR+/HER2+ (PATINA).
- Chemotherapy omission for a third of patients using early PET response (PHERGain).

## Open problems

- Sequencing after T-DXd: no randomised data on which HER2 ADC or TKI works after TOP1-payload failure.
- Interstitial lung disease with T-DXd in curative settings, where patients would otherwise be cured.
- Over-treatment: which patients need pertuzumab, a full year of antibodies, or any chemotherapy at all (PHERGain-2, response-adapted trials).
- Brain metastasis prevention and whether systemic-first strategies preserve cognition.
- HR+/HER2+ ('triple-positive') disease: optimal integration of endocrine therapy, CDK4/6 inhibitors, and HER2 blockade.
- Cardiotoxicity surveillance burden versus event rates in low-risk patients.
- Global access: biosimilars have widened trastuzumab access but pertuzumab, T-DM1, and T-DXd remain unavailable in much of the world.
- HER2 heterogeneity and HER2 conversion at relapse require re-biopsy strategies or HER2 PET.

## Notes

- What this page is called on a report, and why it is your page even if you are also hormone receptor positive. HER2 positive means immunohistochemistry 3+, or 2+ with amplification on in situ hybridisation; the UK asks for the HER2 to chromosome 17 ratio, the HER2 copy number and the chromosome 17 copy number to be reported, and it counts one borderline group as positive that the American guideline counts as negative (ratio 2.0 or more with a copy number below 4). HER2 positivity runs at 13 to 20 percent of early breast cancer (RCPath G148), and most of it is hormone receptor positive too: of American cases with a known subtype, 9.3 percent are hormone receptor-positive and HER2-positive against 4.0 percent HER2-positive alone (SEER 21, 2019 to 2023). If that is you, this page carries the HER2 treatment that decides the backbone and the HR-positive page carries the endocrine treatment that is added to it; five-year relative survival in the two groups was 92.2 and 87.0 percent (SEER 21, 2016 to 2022).

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/HER2-positive_breast_cancer
- Wikipedia: https://en.wikipedia.org/wiki/HER2-positive_breast_cancer
- NCCN Guidelines for Patients and the NCCN breast cancer guideline summary (PMC): https://pmc.ncbi.nlm.nih.gov/articles/PMC13114725/
- SEER Cancer Stat Facts: female breast cancer subtypes (share of cases and five-year relative survival by receptor subtype and stage, SEER 21): https://seer.cancer.gov/statfacts/html/breast-subtypes.html
- Royal College of Pathologists G148: dataset for histopathological reporting of breast disease in surgical excision specimens of breast cancer, version 3, November 2024 (full review due November 2026): https://www.rcpath.org/resourceLibrary/g148-dataset-for-histopathological-reporting-of-breast-disease-in-surgical-excision-specimens-of-breast-cancer.html
- Rakha et al., Journal of Clinical Pathology 2023;76:217 to 227: UK recommendations for HER2 assessment in breast cancer, an update: https://doi.org/10.1136/jcp-2022-208632

## Connected records

- roadmaps: [ADC roadmap: from Mylotarg to bispecific and dual-payload ADCs](https://onco.cc/roadmaps/adc-generations/), [Triple-negative breast cancer roadmap: from a remainder defined by three negative tests to immunotherapy, antibody-drug conjugates and the residual disease problem](https://onco.cc/roadmaps/tnbc-roadmap/)
- pairings: [Early FDG-PET response → chemotherapy omission (HER2+)](https://onco.cc/pairings/pet-adapted-her2-deescalation/), [Tucatinib + trastuzumab + capecitabine for brain metastases](https://onco.cc/pairings/tucatinib-triplet-brain-mets/)
- cancers: [Apocrine carcinoma of the breast](https://onco.cc/cancers/apocrine-carcinoma-breast/), [Brain metastases (secondary brain tumours)](https://onco.cc/cancers/secondary-brain-tumours/), [Breast cancer (all types)](https://onco.cc/cancers/breast-cancer/), [Ductal carcinoma in situ (DCIS)](https://onco.cc/cancers/ductal-carcinoma-in-situ/), [Early HER2-positive breast cancer](https://onco.cc/cancers/her2-positive-early-breast-cancer/), [HER2-low and HER2-ultralow metastatic breast cancer](https://onco.cc/cancers/her2-low-metastatic-breast-cancer/), [HER2-positive breast cancer with brain metastases](https://onco.cc/cancers/her2-positive-breast-brain-metastases/), [HR-positive / HER2-negative breast cancer](https://onco.cc/cancers/breast-hr-positive/), [Inflammatory breast cancer](https://onco.cc/cancers/inflammatory-breast-cancer/), [Invasive breast carcinoma of no special type (invasive ductal carcinoma)](https://onco.cc/cancers/invasive-breast-carcinoma-no-special-type/), [Invasive micropapillary carcinoma of the breast](https://onco.cc/cancers/invasive-micropapillary-carcinoma-breast/), [Male breast cancer](https://onco.cc/cancers/male-breast-cancer/), [Paget disease of the nipple](https://onco.cc/cancers/paget-disease-of-the-nipple/), [Triple-negative breast cancer (TNBC)](https://onco.cc/cancers/tnbc/)
- technologies: [AI scoring of biomarkers and grade on pathology slides](https://onco.cc/technologies/ai-pathology-scoring/), [AI-assisted mammography screening](https://onco.cc/technologies/ai-mammography-screening/), [Antibody-drug conjugate (ADC)](https://onco.cc/technologies/adc/), [Biosimilar manufacturing and comparability](https://onco.cc/technologies/biosimilar-manufacturing/), [Bispecific antibodies](https://onco.cc/technologies/bispecific-antibody/), [Breast reconstruction: implant and autologous, immediate and delayed, and what women report afterwards](https://onco.cc/technologies/rejuv-recon-breast/), [BREAST-Q and the Q-portfolio: measuring what an operation left behind](https://onco.cc/technologies/rejuv-measure-breast-q/), [Cardio-oncology](https://onco.cc/technologies/cardio-oncology/), [CDK4/6 inhibitors](https://onco.cc/technologies/cdk46-inhibitor/), [Dietitian-led weight-loss programmes in HR-positive breast cancer](https://onco.cc/technologies/dietitian-led-weight-loss-breast/), [FDG PET](https://onco.cc/technologies/fdg-pet/), [Heart function after anthracyclines, trastuzumab and chest radiotherapy](https://onco.cc/technologies/cardiotoxicity-surveillance-recovery/), [HER2 PET](https://onco.cc/technologies/her2-pet/), [HER2 tyrosine kinase inhibitors](https://onco.cc/technologies/her2-tyrosine-kinase-inhibitors/), [Hypofractionated radiotherapy](https://onco.cc/technologies/hypofractionated-radiotherapy/), [Mammography & tomosynthesis](https://onco.cc/technologies/mammography/), [Monoclonal antibodies](https://onco.cc/technologies/monoclonal-antibody/), [MRD / molecular residual disease testing](https://onco.cc/technologies/mrd-testing/), [Norton-Simon hypothesis and dose-dense chemotherapy](https://onco.cc/technologies/norton-simon-hypothesis/), [Protecting the heart during anthracycline treatment: dexrazoxane, beta blockers and ACE inhibitors](https://onco.cc/technologies/anthracycline-cardioprotection/), [SBRT / SABR (stereotactic radiotherapy)](https://onco.cc/technologies/sbrt/), [Scalp cooling (cold caps: DigniCap, Paxman)](https://onco.cc/technologies/scalp-cooling/), [Site-specific conjugation & linker chemistry](https://onco.cc/technologies/site-specific-conjugation/), [Small-molecule kinase inhibitors](https://onco.cc/technologies/kinase-inhibitors/), [Strain echocardiography (global longitudinal strain)](https://onco.cc/technologies/strain-echocardiography-gls/), [Surface-guided radiotherapy (SGRT)](https://onco.cc/technologies/surface-guided-radiotherapy/), [The cumulative dose that decides whether it comes back](https://onco.cc/technologies/rejuv-recovery-cumulative-dose/), [Troponin and natriuretic peptide monitoring during cancer treatment](https://onco.cc/technologies/cardiac-biomarker-monitoring/)
- targets: [BIRC5](https://onco.cc/targets/birc5/), [CDK4/6](https://onco.cc/targets/cdk4-6/), [EGFR](https://onco.cc/targets/egfr/), [FCGR2A](https://onco.cc/targets/fcgr2a/), [FCGR3A](https://onco.cc/targets/fcgr3a/), [HER2](https://onco.cc/targets/her2/), [HER3](https://onco.cc/targets/her3/), [HER4 (ERBB4)](https://onco.cc/targets/erbb4/), [PIK3CA / PI3K-alpha](https://onco.cc/targets/pik3ca/), [PTK6 (BRK)](https://onco.cc/targets/ptk6/), [Topoisomerase I (TOP1)](https://onco.cc/targets/top1/)
- drugs: [A166](https://onco.cc/drugs/a166/), [ARX788](https://onco.cc/drugs/arx788/), [Capecitabine](https://onco.cc/drugs/capecitabine/), [Disitamab vedotin](https://onco.cc/drugs/disitamab-vedotin/), [Epirubicin](https://onco.cc/drugs/epirubicin/), [Evorpacept](https://onco.cc/drugs/evorpacept/), [GQ1005](https://onco.cc/drugs/gq1005/), [HB1801](https://onco.cc/drugs/hb1801/), [HER2 IHC and ISH companion assays (HercepTest, PATHWAY 4B5, HER2 Dual ISH)](https://onco.cc/drugs/her2-testing-assays/), [HLX11](https://onco.cc/drugs/hlx11/), [IBI354](https://onco.cc/drugs/ibi354/), [Inavolisib](https://onco.cc/drugs/inavolisib/), [Inetetamab](https://onco.cc/drugs/inetetamab/), [JSKN003](https://onco.cc/drugs/jskn003/), [KN026](https://onco.cc/drugs/kn026/), [Lapatinib](https://onco.cc/drugs/lapatinib/), [Margetuximab](https://onco.cc/drugs/margetuximab/), [Neratinib](https://onco.cc/drugs/neratinib/), [Paclitaxel / nab-paclitaxel](https://onco.cc/drugs/paclitaxel/), [Palbociclib](https://onco.cc/drugs/palbociclib/), [Pegulicianine](https://onco.cc/drugs/pegulicianine/), [Pertuzumab](https://onco.cc/drugs/pertuzumab/), [Pyrotinib](https://onco.cc/drugs/pyrotinib/), [RO7771950](https://onco.cc/drugs/ro7771950/), [RPH-051](https://onco.cc/drugs/rph-051/), [TQB2102](https://onco.cc/drugs/tqb2102/), [Transpara](https://onco.cc/drugs/transpara/), [Trastuzumab](https://onco.cc/drugs/trastuzumab/), [Trastuzumab biosimilars](https://onco.cc/drugs/trastuzumab-biosimilars/), [Trastuzumab brengitecan](https://onco.cc/drugs/trastuzumab-brengitecan/), [Trastuzumab deruxtecan](https://onco.cc/drugs/trastuzumab-deruxtecan/), [Trastuzumab duocarmazine](https://onco.cc/drugs/trastuzumab-duocarmazine/), [Trastuzumab emtansine](https://onco.cc/drugs/trastuzumab-emtansine/), [Trastuzumab pamirtecan](https://onco.cc/drugs/trastuzumab-pamirtecan/), [Trastuzumab rezetecan](https://onco.cc/drugs/trastuzumab-rezetecan/), [Tucatinib](https://onco.cc/drugs/tucatinib/), [Zanidatamab](https://onco.cc/drugs/zanidatamab/), [Zanidatamab zovodotin](https://onco.cc/drugs/zanidatamab-zovodotin/)
- companies: [3SBio](https://onco.cc/companies/3sbio/), [Ambrx](https://onco.cc/companies/ambrx/), [AstraZeneca](https://onco.cc/companies/astrazeneca/), [Ataraxis AI](https://onco.cc/companies/ataraxis-ai/), [Austrian Breast & Colorectal Cancer Study Group](https://onco.cc/companies/abcsg/), [Breast Cancer Trials](https://onco.cc/companies/breast-cancer-trials/), [Breast International Group (BIG)](https://onco.cc/companies/big/), [BridgeBio Oncology Therapeutics](https://onco.cc/companies/bridgebio-oncology-therapeutics/), [Callio Therapeutics](https://onco.cc/companies/callio-therapeutics/), [Clear Gene](https://onco.cc/companies/clear-gene/), [Criterium](https://onco.cc/companies/criterium/), [Daiichi Sankyo](https://onco.cc/companies/daiichi-sankyo/), [Danish Breast Cancer Group](https://onco.cc/companies/dbcg/), [ETOP IBCSG Partners Foundation](https://onco.cc/companies/etop-ibcsg/), [Galena Biopharma](https://onco.cc/companies/galena-biopharma/), [GEICAM Spanish Breast Cancer Group](https://onco.cc/companies/geicam/), [GeneQuantum Healthcare (Suzhou)](https://onco.cc/companies/genequantum-healthcare-suzhou/), [Ibex Medical Analytics](https://onco.cc/companies/ibex-medical-analytics/), [iSono Health](https://onco.cc/companies/isono-health/), [Jazz Pharmaceuticals](https://onco.cc/companies/jazz/), [Jiangsu Hengrui Pharmaceuticals](https://onco.cc/companies/hengrui/), [Johnson & Johnson](https://onco.cc/companies/johnson-johnson/), [Kheiron Medical Technologies](https://onco.cc/companies/kheiron-medical-technologies/), [Korean Cancer Study Group](https://onco.cc/companies/kcsg/), [Lumicell](https://onco.cc/companies/lumicell/), [MacroGenics](https://onco.cc/companies/macrogenics/), [NearWave](https://onco.cc/companies/nearwave/), [NSABP Foundation](https://onco.cc/companies/nsabp-foundation/), [Organon & Co.](https://onco.cc/companies/organon/), [Outcomes4Me](https://onco.cc/companies/outcomes4me/), [Perimeter Medical Imaging AI](https://onco.cc/companies/perimeter-medical-imaging-ai/), [Pfizer (incl. Seagen)](https://onco.cc/companies/pfizer/), [Precirix](https://onco.cc/companies/precirix/), [Proxygen](https://onco.cc/companies/proxygen/), [Puma Biotechnology](https://onco.cc/companies/puma-biotechnology/), [RemeGen](https://onco.cc/companies/remegen/), [Roche / Genentech](https://onco.cc/companies/roche-genentech/), [Samsung Bioepis](https://onco.cc/companies/samsung-bioepis/), [SOLTI Cancer Research Group](https://onco.cc/companies/solti/), [SystImmune / Sichuan Biokin](https://onco.cc/companies/systimmune/), [Therapixel](https://onco.cc/companies/therapixel/), [Vara](https://onco.cc/companies/vara/), [Volpara Health](https://onco.cc/companies/volpara-health/), [West Japan Oncology Group](https://onco.cc/companies/wjog/), [Zymeworks](https://onco.cc/companies/zymeworks/)
- pathways: [Breast cancer (KEGG map)](https://onco.cc/pathways/breast-cancer-signalling/), [p53 / RB / cell-cycle checkpoint](https://onco.cc/pathways/p53-cell-cycle/), [PI3K / AKT / mTOR](https://onco.cc/pathways/pi3k-akt-mtor/), [RAS / RAF / MEK / ERK (MAPK)](https://onco.cc/pathways/ras-mapk/), [Receptor tyrosine kinase activation](https://onco.cc/pathways/rtk-activation/), [The blood-brain barrier & brain metastasis](https://onco.cc/pathways/blood-brain-barrier-metastasis/)
- terms: [ADC sequencing](https://onco.cc/terms/adc-sequencing/), [AJCC 8th edition prognostic stage for breast cancer](https://onco.cc/terms/ajcc-prognostic-stage-breast/), [Biosimilar](https://onco.cc/terms/biosimilar/), [Brain metastases (intracranial disease)](https://onco.cc/terms/brain-metastases/), [Breast conservation or mastectomy](https://onco.cc/terms/breast-conserving-surgery-versus-mastectomy/), [Breast implant-associated anaplastic large cell lymphoma](https://onco.cc/terms/bia-alcl/), [Breast reconstruction](https://onco.cc/terms/breast-reconstruction/), [Deauville score and PET-adapted therapy](https://onco.cc/terms/deauville/), [Deep inspiration breath-hold (DIBH)](https://onco.cc/terms/deep-inspiration-breath-hold/), [Doing less to the armpit](https://onco.cc/terms/axillary-surgery-de-escalation/), [Drugs before or after the operation](https://onco.cc/terms/neoadjuvant-versus-adjuvant-breast/), [Dual HER2 blockade](https://onco.cc/terms/dual-her2-blockade/), [Grade, stage and receptor status: three different things on one breast report](https://onco.cc/terms/grade-stage-receptor-breast/), [HER2 testing in the UK: reflex ISH, the ratio against the copy number, and where the UK differs from ASCO/CAP](https://onco.cc/terms/her2-testing-uk-breast/), [HER2-positive (IHC 3+ or ISH-amplified)](https://onco.cc/terms/her2-positive/), [HER2-positive brain metastases](https://onco.cc/terms/her2-brain-metastases/), [Interstitial lung disease (ILD) / pneumonitis](https://onco.cc/terms/ild/), [Leaving radiotherapy out](https://onco.cc/terms/radiotherapy-omission-early-breast-cancer/), [Lumpectomy (breast-conserving surgery)](https://onco.cc/terms/lumpectomy/), [Lymphoedema after breast cancer treatment](https://onco.cc/terms/breast-cancer-related-lymphoedema/), [Mastectomy](https://onco.cc/terms/mastectomy/), [Nottingham grade (breast cancer grade 1, 2 and 3)](https://onco.cc/terms/nottingham-grade/), [Oncoplastic breast surgery](https://onco.cc/terms/oncoplastic-breast-surgery/), [Partial-breast irradiation](https://onco.cc/terms/partial-breast-irradiation/), [Pathologic complete response (pCR)](https://onco.cc/terms/pcr/), [Radiotherapy after mastectomy](https://onco.cc/terms/post-mastectomy-radiotherapy/), [Receptor conversion: when the receptors change between the primary and a recurrence](https://onco.cc/terms/receptor-conversion-breast/), [Targeted axillary dissection](https://onco.cc/terms/targeted-axillary-dissection/), [The WHO classification of breast tumours, and what the 6th edition changed](https://onco.cc/terms/who-breast-classification/), [Trastuzumab cardiotoxicity](https://onco.cc/terms/trastuzumab-cardiotoxicity/), [Tumour bed boost](https://onco.cc/terms/tumour-bed-boost/), [Which staging edition a breast report uses: UICC TNM 8, TNM 9 and the AJCC prognostic stage](https://onco.cc/terms/tnm-breast-cancer-editions/)
- trials: [A Clinical Study of Neoadjuvant Treatment With TQB2102 for Injection for Human Epidermal Growth Factor Receptor 2 (HER2) Positive Breast Cancer](https://onco.cc/trials/nct07043725/), [A Clinical Study of TQB2102 Versus Docetaxel Plus Trastuzumab and Pertuzumab in the Treatment of HER2 Positive Recurrent or Metastatic Breast Cancer](https://onco.cc/trials/nct07003074/), [A Phase 1 Trial of ZN-A-1041 Enteric Capsules or Combination in Participants With Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Advanced So](https://onco.cc/trials/nct05593094/), [A Phase 1b/2 Study of T-DXd Combinations in HER2-positive Metastatic Breast Cancer](https://onco.cc/trials/nct04538742/), [A Phase 2 Neoadjuvant Study of Zanidatamab in Combination With Chemotherapy in Participants With HER2-positive Breast Cancer](https://onco.cc/trials/nct07102381/), [A Phase II Study of HLX22 in Combination With Trastuzumab Deruxtecan in HER2-low, Hormone Receptor Positive Locally Advanced or Metastatic Breast Cancer Patients](https://onco.cc/trials/nct06832202/), [A Phase III Study of KN026 in Combination With HB1801 ± Carboplatin as Neoadjuvant Treatment for Early or Locally Advanced HER2-Positive Breast Cancer](https://onco.cc/trials/nct06747338/), [A Phase III Study of KN026 in Combination With HB1801 as Adjuvant Therapy for Resectable HER2-Positive Breast Cancer](https://onco.cc/trials/nct07441460/), [A Phase III Study of SHR-A1811 Injection With or Without Pertuzumab in HER2-Positive Recurrent or Metastatic Breast Cancer](https://onco.cc/trials/nct06057610/), [A Phase III, Active-Controlled Study of SHR-A1811 Versus Trastuzumab Emtansine (T-DM1) in HER2-Positive Primary Breast Cancer Participants With Residual Invasive Disease Following Neoadjuvant Therapy](https://onco.cc/trials/nct06126640/), [A Study Comparing BL-M07D1 With DS-8201 in Patients With HR-Positive, HER2-Low Expressing Recurrent/Metastatic Breast Cancer](https://onco.cc/trials/nct07678957/), [A Study Comparing BL-M07D1 With T-DM1 in Patients With Unresectable Locally Advanced or Metastatic HER2-positive Breast Cancer](https://onco.cc/trials/nct06316531/), [A Study Comparing the Efficacy and Safety of Zanidatamab to Trastuzumab, Each in Combination With Physician's Choice Chemotherapy, for the Treatment o](https://onco.cc/trials/nct06435429/), [A Study Evaluating the Efficacy and Safety of Adjuvant Atezolizumab or Placebo and Trastuzumab Emtansine for Participants With HER2-Positive Breast Cancer at High Risk of Recurrence Following Preoperative Therapy](https://onco.cc/trials/nct04873362/), [A Study of A166 in Patients With HER2-Positive Unresectable or Metastatic Breast Cancer](https://onco.cc/trials/nct07299825/), [A Study of A166 Versus Trastuzumab Emtansine (T-DM1) in Patients With HER2-Positive Unresectable or Metastatic Breast Cancer Previously Treated With Trastuzumab and Taxane Therapy](https://onco.cc/trials/nct06968585/), [A Study of BL-M07D1 Combined With Pertuzumab Versus Docetaxel Plus Trastuzumab and Pertuzumab in Patients With First-line HER2-positive Recurrent or M](https://onco.cc/trials/nct07518173/), [A Study of BL-M07D1 Versus Investigator's Choice of Chemotherapy in Patients With HER2-low Recurrent/Metastatic Breast Cancer](https://onco.cc/trials/nct06957886/), [A Study of BL-M07D1 Versus T-DM1 in the Adjuvant Treatment of HER2-positive Breast Cancer With Residual Invasive Cancer After Neoadjuvant Therapy](https://onco.cc/trials/nct06830889/), [A Study of BL-M07D1 With or Without Pertuzumab Versus Docetaxel + Carboplatin + Trastuzumab + Pertuzumab in Neoadjuvant Therapy for HER2-Positive Brea](https://onco.cc/trials/nct06891833/), [A Study of BL-M07D1, BL-M07D1+Pertuzumab and BL-M07D1+Pertuzumab+Docetaxel in Patients With Unresectable Locally Advanced or Metastatic HER2-positive ](https://onco.cc/trials/nct06445400/), [A Study of DB-1303/BNT323 vs Investigator's Choice Chemotherapy in HER2-Low, Hormone Receptor Positive Metastatic Breast Cancer (DYNASTY-Bre](https://onco.cc/trials/nct06018337/), [A Study of Disitamab Vedotin With Other Anticancer Drugs in Solid Tumors](https://onco.cc/trials/nct06157892/), [A Study of Neoadjuvant Treatment With TQB2102 for Injection for Human Epidermal Growth Factor Receptor 2 (HER2) Positive Breast Cancer](https://onco.cc/trials/nct06198751/), [A Study of the Efficacy, Safety and Pharmacokinetics of RPH-051 and Perjeta® in Combination With Trastuzumab and Docetaxel as the 1st Line Therapy in Patients With HER2-positive Breast Cancer](https://onco.cc/trials/nct07386938/), [A Study to Compare DB-1303/BNT323 Versus T-DM1 in Breast Cancer](https://onco.cc/trials/nct06265428/), [A Study to Evaluate HLX22 in Combination With HLX87 in Patients With HER2-Positive Recurrent or Metastatic Breast Cancer](https://onco.cc/trials/nct07294508/), [A Study to Evaluate the Efficacy and Safety of HLX11 vs. EU-Perjeta® in the Neoadjuvant Therapy of HER2-Positive and HR-Negative Early-stage or Locally Advanced Breast Cancer](https://onco.cc/trials/nct05346224/), [A Study to Evaluate the Efficacy and Safety of Inavolisib in Combination With Phesgo Versus Placebo in Combination With Phesgo in Participants With PIK3CA-Mutated HER2-Positive Locally Advanced or Metastatic Breast Cancer](https://onco.cc/trials/nct05894239/), [A Trial Comparing GQ1005 and T-DM1 in Patients With HER2-Positive Unresectable or Metastatic Breast Cancer](https://onco.cc/trials/nct07673029/), [A Trial of SHR-A1811 Compared to Other Antitumor Therapies as Neoadjuvant Treatments in Early-stage or Locally Advanced HER2-positive Breast Cancer](https://onco.cc/trials/nct07196774/), [ACE-Breast-02](https://onco.cc/trials/ace-breast-02/), [ACOSOG Z0011 (Alliance)](https://onco.cc/trials/acosog-z0011/), [ACOSOG Z1071 (Alliance)](https://onco.cc/trials/acosog-z1071/), [ALMANAC (Axillary Lymphatic Mapping Against Nodal Axillary Clearance)](https://onco.cc/trials/almanac/), [AMAROS (EORTC 10981-22023)](https://onco.cc/trials/amaros/), [APHINITY](https://onco.cc/trials/aphinity/), [APT (adjuvant paclitaxel-trastuzumab)](https://onco.cc/trials/apt-trial/), [ARX788 in HER2-positive, Metastatic Breast Cancer Subjects (ACE-Breast-03)](https://onco.cc/trials/nct04829604/), [ASPEN-09-03: A Study of Evorpacept in Combination With Trastuzumab and Chemotherapy in Metastatic HER2-Positive Breast Cancer](https://onco.cc/trials/nct07007559/), [ATEMPT](https://onco.cc/trials/atempt/), [ATNEC](https://onco.cc/trials/atnec/), [Best-BRA](https://onco.cc/trials/best-bra/), [BWEL (Breast Cancer Weight Loss, Alliance A011401)](https://onco.cc/trials/bwel/), [CLEOPATRA](https://onco.cc/trials/cleopatra/), [Clinical Study of the Efficacy and Safety of BCD-178 and Perjeta® as Neoadjuvant Therapy of HER2-Positive Breast Cancer](https://onco.cc/trials/nct05802225/), [Clinical Trial of Alpelisb and Tucatinib in Patients With PIK3CA-Mutant HER2+ Metastatic Breast Cancer.](https://onco.cc/trials/nct05230810/), [Clinical Trial of TQB2102 for Injection Versus Trastuzumab Emtansine for Injection in HER2-positive Advanced Breast Cancer](https://onco.cc/trials/nct07008976/), [DBCG 82b and 82c](https://onco.cc/trials/dbcg-82bc/), [DESTINY-Breast03](https://onco.cc/trials/destiny-breast03/), [DESTINY-Breast05](https://onco.cc/trials/destiny-breast05/), [DESTINY-Breast09](https://onco.cc/trials/destiny-breast09/), [DESTINY-Breast11](https://onco.cc/trials/destiny-breast11/), [DESTINY-Breast12](https://onco.cc/trials/destiny-breast12/), [DP303c Versus Trastuzumab Emtansine in in Patients With HER2-positive Advanced Breast Cancer](https://onco.cc/trials/nct06313086/), [Dual-Target CAR-NK Cells for Advanced Breast Cancer (HER2+ and TNBC)](https://onco.cc/trials/nct07486089/), [Dual-Target CAR-NK Cells for Advanced Breast Cancer HER2+ TNBC](https://onco.cc/trials/nct07510802/), [DV in Combination With Pertuzumab With or Without Toripalimab Neoadjuvant Therapy With HER2-positive Breast Cancer](https://onco.cc/trials/nct06178159/), [Efficacy and Safety of KN026 in Combination With HB1801 in the First-line Treatment of Subjects With HER2-positive Recurrent or Metastatic Breast Cancer](https://onco.cc/trials/nct05838066/), [Efficacy and Safety Study of Disitamab Vedotin + RC148 vs. Albumin-Paclitaxone ± Toripalimab in HR-/HER2-low Breast Cancer](https://onco.cc/trials/nct06642545/), [EORTC 10801](https://onco.cc/trials/eortc-10801/), [EORTC 22881-10882 (boost against no boost)](https://onco.cc/trials/eortc-22881-boost/), [EORTC 22922/10925](https://onco.cc/trials/eortc-22922/), [FAST (5-fraction whole-breast radiotherapy)](https://onco.cc/trials/fast-trial/), [FAST-Forward](https://onco.cc/trials/fast-forward/), [HER2CLIMB](https://onco.cc/trials/her2climb/), [HER2CLIMB-02](https://onco.cc/trials/her2climb-02/), [HER2CLIMB-05](https://onco.cc/trials/her2climb-05/), [HERA, NSABP B-31 & NCCTG N9831 (adjuvant trastuzumab)](https://onco.cc/trials/hera-b31-n9831/), [HORIZON-Breast01](https://onco.cc/trials/horizon-breast01/), [I-SPY 1 (CALGB 150007/150012, ACRIN 6657)](https://onco.cc/trials/i-spy-1/), [I-SPY 2](https://onco.cc/trials/i-spy-2/), [I-SPY 2.2](https://onco.cc/trials/i-spy-2-2/), [IBCSG 23-01](https://onco.cc/trials/ibcsg-23-01/), [IBI354 With or Without Pertuzumab Versus Taxane, Trastuzumab and Pertuzumab in HER2-positive Metastatic Breast Cancer](https://onco.cc/trials/nct07377643/), [iBRA (implant Breast Reconstruction evAluation)](https://onco.cc/trials/ibra-study/), [IMPORT LOW](https://onco.cc/trials/import-low/), [INSEMA (Intergroup Sentinel Mamma)](https://onco.cc/trials/insema/), [INSITE](https://onco.cc/trials/insite/), [JSKN003 Versus Trastuzumab Emtansine (T-DM1) for HER2-Positive, Advanced Breast Cancer](https://onco.cc/trials/nct06846437/), [KATHERINE](https://onco.cc/trials/katherine/), [KRISTINE](https://onco.cc/trials/kristine/), [MARGetuximab Or Trastuzumab (MARGOT)](https://onco.cc/trials/nct04425018/), [Mastectomy Reconstruction Outcomes Consortium (MROC)](https://onco.cc/trials/mroc/), [Milan I (quadrantectomy against radical mastectomy)](https://onco.cc/trials/milan-i/), [NALA](https://onco.cc/trials/nala/), [NCIC MA.20](https://onco.cc/trials/ma-20/), [Neoadjuvant Study of DV in Combination Toripalimab or Sequence Chemotherapy in HR-negative, HER2 Low-expressing Breast Cancer](https://onco.cc/trials/nct06227117/), [NeoSphere](https://onco.cc/trials/neosphere/), [NSABP B-04](https://onco.cc/trials/nsabp-b04/), [NSABP B-06](https://onco.cc/trials/nsabp-b06/), [NSABP B-32](https://onco.cc/trials/nsabp-b32/), [NSABP B-39/RTOG 0413](https://onco.cc/trials/nsabp-b39/), [NSABP B-51 / RTOG 1304](https://onco.cc/trials/nsabp-b51/), [PATINA](https://onco.cc/trials/patina/), [Peritumoral lidocaine before breast cancer surgery (Tata Memorial)](https://onco.cc/trials/lidocaine-peritumoral-tmh/), [PERSEPHONE](https://onco.cc/trials/persephone/), [PHERGain](https://onco.cc/trials/phergain/), [POSNOC](https://onco.cc/trials/posnoc/), [Pre-BRA (pre-pectoral breast reconstruction evaluation)](https://onco.cc/trials/pre-bra/), [RADCOMP](https://onco.cc/trials/radcomp/), [RAPID (accelerated partial-breast irradiation)](https://onco.cc/trials/rapid/), [RC48 Combined With Chemotherapy in HER2-Positive Advanced Breast Cancer Patients With Prior TOP1i-ADC Failure](https://onco.cc/trials/nct07366840/), [RO7771950 Versus Tucatinib in Combination With Trastuzumab and Capecitabine in People With Locally Advanced or Metastatic Breast Cancer That is Human Epidermal Growth Factor Receptor 2 (HER2)-Positive](https://onco.cc/trials/nct07413939/), [SENOMAC](https://onco.cc/trials/senomac/), [SOUND (Sentinel Node vs Observation After Axillary Ultra-Sound)](https://onco.cc/trials/sound/), [START-A (UK Standardisation of Breast Radiotherapy, trial A)](https://onco.cc/trials/start-a/), [START-B (UK Standardisation of Breast Radiotherapy)](https://onco.cc/trials/start-b/), [Study BT8009-100 in Subjects With Nectin-4 Expressing Advanced Malignancies](https://onco.cc/trials/nct04561362/), [Study of Alpelisib (BYL719) in Combination With Trastuzumab and Pertuzumab as Maintenance Therapy in Patients With HER2-positive Advanced Breast Cancer With a PIK3CA Mutation](https://onco.cc/trials/nct04208178/), [Study of Patritumab Deruxtecan With Other Anticancer Agents in Participants With HER2 Positive Breast Cancer That Has Spread and Cannot Be Surgically Removed (MK-1022-009)](https://onco.cc/trials/nct06686394/), [SUPREMO (BIG 2-04)](https://onco.cc/trials/supremo/), [Targeted axillary dissection (MD Anderson prospective study)](https://onco.cc/trials/targeted-axillary-dissection-md-anderson/), [TARGIT-A (targeted intraoperative radiotherapy)](https://onco.cc/trials/targit-a/), [TMIST (Tomosynthesis Mammographic Imaging Screening Trial)](https://onco.cc/trials/tmist/), [To Evaluate the Efficacy and Safety of Disitamab Vedotin Combined With Toripalimab Sequential Chemotherapy as Neoadjuvant Treatment in Patients With HR-positive, HER2-low Breast Cancer](https://onco.cc/trials/nct06389006/), [TQB2930 Injection for the Treatment of HER2-positive Advanced Breast Cancer](https://onco.cc/trials/nct07047365/), [TRAIN-2](https://onco.cc/trials/train-2/), [Trastuzumab Deruxtecan (T-DXd) in Patients Who Have Hormone Receptor-negative and Hormone Receptor-positive HER2-low or HER2 IHC 0 Metastatic Breast Cancer](https://onco.cc/trials/nct05950945/), [TUXEDO-1](https://onco.cc/trials/tuxedo-1/)
- journals: [Breast cancer](https://onco.cc/journals/breast-cancer-jbcs/), [Breast cancer research](https://onco.cc/journals/breast-cancer-research/), [Breast cancer research and treatment](https://onco.cc/journals/breast-cancer-research-and-treatment/), [Clinical breast cancer](https://onco.cc/journals/clinical-breast-cancer/), [Journal of breast imaging](https://onco.cc/journals/journal-of-breast-imaging/), [Journal of mammary gland biology and neoplasia](https://onco.cc/journals/journal-of-mammary-gland-biology-and-neoplasia/), [The Breast](https://onco.cc/journals/the-breast/), [The breast journal](https://onco.cc/journals/the-breast-journal/)
- ideas: [A risk-stratified cardio-oncology pathway for everyone receiving heart-toxic cancer therapy](https://onco.cc/ideas/idea-acc-risk-stratified-cardio-oncology-pathway/), [A standard platform to get drugs into the brain: focused ultrasound plus shuttle-engineered therapeutics](https://onco.cc/ideas/idea-moon-brain-delivery-platform/), [An organotropism atlas that predicts where a cancer will spread](https://onco.cc/ideas/idea-bio2-organotropism-atlas/), [Biomarker-guided cardioprotection for everyone on cardiotoxic cancer therapy](https://onco.cc/ideas/idea-moon-cardioprotection-by-default/), [Brain metastases included by default in every solid-tumour trial](https://onco.cc/ideas/idea-tr1-brain-mets-default-included/), [Build a human model of the barrier that guards the brain fluid](https://onco.cc/ideas/idea-bio2-blood-csf-barrier-model/), [Can T-DXd alone cure early HER2-positive disease?](https://onco.cc/ideas/idea-tdxd-first-then-nothing/), [Deliver CAR-T cells straight into the fluid around the brain](https://onco.cc/ideas/idea-bio2-intraventricular-car-t/), [Fund trials that test shorter courses of the most expensive adjuvant drugs](https://onco.cc/ideas/idea-cost-shorter-course-trials/), [One-stop breast clinics: imaging, biopsy and a preliminary answer in a single visit](https://onco.cc/ideas/idea-acc-one-stop-breast-diagnostic-clinic/), [Prevention trials aimed only at brain metastasis](https://onco.cc/ideas/idea-bio2-brain-met-prevention-trials/), [Public country dashboards for the three WHO breast cancer targets](https://onco.cc/ideas/idea-acc-gbci-country-dashboards/), [Re-test the metastasis, not the old primary, before every change of treatment](https://onco.cc/ideas/idea-bio1-rebiopsy-before-switch/), [Read the spinal fluid to track brain tumours without opening the skull](https://onco.cc/ideas/idea-bio2-csf-ctdna-monitoring/), [Reduce the dose once the cancer responds: response-adapted de-escalation trials](https://onco.cc/ideas/idea-tr1-response-adapted-dose-reduction/), [Sequencing HER2 ADCs by payload after T-DXd](https://onco.cc/ideas/idea-her2-adc-sequencing-payload/), [Systemic-first management of HER2-positive brain metastases](https://onco.cc/ideas/idea-cns-first-adc-strategy/), [Treat brain metastases as a disease with its own trials programme](https://onco.cc/ideas/idea-fund-brain-metastases-programme/), [Use the brain's own transport door to carry antibody drugs across](https://onco.cc/ideas/idea-bio2-transferrin-shuttle-adc/), [WHO prequalification plus pooled demand to push biosimilar prices below 10% of the originator](https://onco.cc/ideas/idea-acc-biosimilar-prequalification-pool/)
- key papers: [Al-Hajj 2003: prospective identification of tumorigenic breast cancer cells](https://onco.cc/key-papers/paper-al-hajj-breast-cancer-stem-cells-pnas-2003/), [Breast Cancer, Version 4.2026, NCCN Clinical Practice Guidelines In Oncology](https://onco.cc/key-papers/paper-nccn-breast-cancer-v4-2026-jnccn-2026/), [DESTINY-Breast03: trastuzumab deruxtecan beats T-DM1 as second-line treatment of HER2-positive metastatic breast cancer](https://onco.cc/key-papers/paper-destiny-breast03-nejm-2022/), [Early breast cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up](https://onco.cc/key-papers/paper-esmo-early-breast-cancer-guideline-ann-oncol-2024/), [ESMO Clinical Practice Guideline for the diagnosis, staging and treatment of patients with metastatic breast cancer](https://onco.cc/key-papers/paper-esmo-metastatic-breast-cancer-guideline-ann-oncol-2021/), [Gene expression patterns of breast carcinomas distinguish tumor subclasses with clinical implications](https://onco.cc/key-papers/paper-sorlie-breast-carcinoma-subclasses-pnas-2001/), [KATHERINE: switching to T-DM1 when HER2-positive breast cancer survives pre-surgery treatment](https://onco.cc/key-papers/paper-katherine-nejm-2019/), [Long-Term Prognostic Risk After Neoadjuvant Chemotherapy Associated With Residual Cancer Burden and Breast Cancer Subtype](https://onco.cc/key-papers/paper-symmans-rcb-long-term-prognosis-subtype-jco-2017/), [MASAI: AI-supported mammography screening finds more cancers with half the radiologist workload](https://onco.cc/key-papers/paper-masai-lancet-oncol-2023/), [Molecular portraits of human breast tumours](https://onco.cc/key-papers/paper-perou-molecular-portraits-breast-tumours-nature-2000/), [Pathological complete response and long-term clinical benefit in breast cancer: the CTNeoBC pooled analysis](https://onco.cc/key-papers/paper-cortazar-ctneobc-pcr-pooled-analysis-lancet-2014/), [Residual cancer burden after neoadjuvant chemotherapy and long-term survival outcomes in breast cancer: a multicentre pooled analysis of 5161 patients](https://onco.cc/key-papers/paper-yau-rcb-pooled-analysis-5161-lancet-oncol-2022/), [SCALP: scalp cooling to prevent hair loss during chemotherapy for early breast cancer](https://onco.cc/key-papers/paper-scalp-trial-jama-2017/), [Slamon 1987: HER2 gene amplification marks an aggressive form of breast cancer](https://onco.cc/key-papers/paper-slamon-her2-amplification-science-1987/), [Slamon 1989: HER2/neu in human breast and ovarian cancer](https://onco.cc/key-papers/paper-slamon-her2-breast-ovarian-science-1989/), [Slamon 2001: adding trastuzumab to chemotherapy for HER2-positive metastatic breast cancer](https://onco.cc/key-papers/paper-slamon-trastuzumab-nejm-2001/), [Tailoring treatment to cancer risk and patient preference: the 2025 St Gallen International Breast Cancer Consensus Statement on individualizing therapy for patients with early breast cancer](https://onco.cc/key-papers/paper-st-gallen-2025-consensus-ann-oncol-2025/), [The self-experiment: a virologist treated her own recurrent breast cancer with two viruses she made in her own laboratory](https://onco.cc/key-papers/paper-halassy-self-experiment-ovt-vaccines-2024/), [Understanding breast cancer complexity to improve patient outcomes: The St Gallen International Consensus Conference for the Primary Therapy of Individuals with Early Breast Cancer 2023](https://onco.cc/key-papers/paper-st-gallen-2023-consensus-ann-oncol-2023/), [US incidence of breast cancer subtypes defined by joint hormone receptor and HER2 status](https://onco.cc/key-papers/paper-howlader-us-incidence-breast-subtypes-jnci-2014/)
- institutions: [Breast Cancer Research Foundation](https://onco.cc/institutions/bcrf/), [Centre Léon Bérard](https://onco.cc/institutions/centre-leon-berard/), [Champalimaud Foundation, Champalimaud Clinical Centre](https://onco.cc/institutions/champalimaud/), [Duke Cancer Institute](https://onco.cc/institutions/duke-cancer-institute/), [Fondazione Michelangelo](https://onco.cc/institutions/fondazione-michelangelo/), [Georgetown Lombardi Comprehensive Cancer Center](https://onco.cc/institutions/georgetown-lombardi/), [Hospital del Mar / Hospital del Mar Research Institute](https://onco.cc/institutions/hospital-del-mar/), [IEO (European Institute of Oncology)](https://onco.cc/institutions/ieo-milan/), [Institut Jules Bordet](https://onco.cc/institutions/institut-jules-bordet/), [Instituto Alexander Fleming](https://onco.cc/institutions/instituto-alexander-fleming/), [IRCCS Ospedale San Raffaele](https://onco.cc/institutions/san-raffaele/), [Istituto di Candiolo IRCCS (FPO)](https://onco.cc/institutions/candiolo/), [Istituto Oncologico Veneto IRCCS](https://onco.cc/institutions/iov-veneto/), [Mayo Clinic Comprehensive Cancer Center in Florida](https://onco.cc/institutions/mayo-clinic-florida/), [National Taiwan University Hospital](https://onco.cc/institutions/ntuh/), [Orlando Health Cancer Institute](https://onco.cc/institutions/orlando-health-cancer-institute/), [Rosalind and Morris Goodman Cancer Institute, McGill University](https://onco.cc/institutions/mcgill-goodman/), [Tianjin Medical University Cancer Institute and Hospital](https://onco.cc/institutions/tmucih/), [Union Hospital, Tongji Medical College](https://onco.cc/institutions/union-hospital-wuhan/), [Weizmann Institute of Science](https://onco.cc/institutions/weizmann/)
- people: [Aleix Prat](https://onco.cc/people/aleix-prat/), [Andrew Wardley](https://onco.cc/people/andrew-wardley/), [Anna Sapino](https://onco.cc/people/anna-sapino/), [Barbara Bradfield](https://onco.cc/people/barbara-bradfield/), [Binghe Xu](https://onco.cc/people/xu-binghe/), [Carlos Barrios](https://onco.cc/people/barrios-carlos/), [Carlos Caldas](https://onco.cc/people/carlos-caldas/), [Charles E. Geyer Jr.](https://onco.cc/people/charles-geyer/), [Charles M. Perou](https://onco.cc/people/charles-perou/), [Clifford A. Hudis](https://onco.cc/people/clifford-hudis/), [Cristina Saura](https://onco.cc/people/cristina-saura/), [David Cameron](https://onco.cc/people/david-cameron/), [Debu Tripathy](https://onco.cc/people/debu-tripathy/), [Dennis J. Slamon](https://onco.cc/people/dennis-slamon/), [Derrick S. Haslem](https://onco.cc/people/derrick-haslem/), [Donna McKay](https://onco.cc/people/donna-mckay/), [Eleftherios P. Mamounas](https://onco.cc/people/eleftherios-mamounas/), [Eric P. Winer](https://onco.cc/people/eric-winer/), [Eva Ciruelos](https://onco.cc/people/eva-ciruelos/), [Evandro de Azambuja](https://onco.cc/people/evandro-de-azambuja/), [Fei Ma](https://onco.cc/people/ma-fei/), [Gunter von Minckwitz](https://onco.cc/people/gunter-von-minckwitz/), [Helena Earl](https://onco.cc/people/helena-earl/), [Ian E. Krop](https://onco.cc/people/ian-krop/), [Isabel T. Rubio](https://onco.cc/people/isabel-rubio/), [Jame Abraham](https://onco.cc/people/jame-abraham/), [Javier Cortés](https://onco.cc/people/javier-cortes/), [Joaquín Arribas](https://onco.cc/people/joaquin-arribas/), [Jonas Bergh](https://onco.cc/people/jonas-bergh/), [Joohyuk Sohn](https://onco.cc/people/sohn-joohyuk/), [José Baselga](https://onco.cc/people/jose-baselga/), [Kan Yonemori](https://onco.cc/people/yonemori-kan/), [Laura J. Esserman](https://onco.cc/people/laura-esserman/), [Luca Gianni](https://onco.cc/people/luca-gianni/), [Marek Svoboda](https://onco.cc/people/marek-svoboda/), [Martine Piccart](https://onco.cc/people/martine-piccart/), [Michael Gnant](https://onco.cc/people/michael-gnant/), [Monica Morrow](https://onco.cc/people/monica-morrow/), [Nadia Harbeck](https://onco.cc/people/nadia-harbeck/), [Nancy U. Lin](https://onco.cc/people/nancy-lin/), [Norman Wolmark](https://onco.cc/people/norman-wolmark/), [Priya Rastogi](https://onco.cc/people/priya-rastogi/), [Rashmi K. Murthy](https://onco.cc/people/rashmi-murthy/), [Rebecca Dent](https://onco.cc/people/rebecca-dent/), [Rupert Bartsch](https://onco.cc/people/rupert-bartsch/), [Sandra M. Swain](https://onco.cc/people/sandra-swain/), [Sara A. Hurvitz](https://onco.cc/people/sara-hurvitz/), [Sara López-Tarruella](https://onco.cc/people/sara-lopez-tarruella/), [Sara M. Tolaney](https://onco.cc/people/sara-tolaney/), [Shanu Modi](https://onco.cc/people/shanu-modi/), [Shinji Ohno](https://onco.cc/people/ohno-shinji/), [Sibylle Loibl](https://onco.cc/people/sibylle-loibl/), [Sung-Bae Kim](https://onco.cc/people/kim-sung-bae/), [Sunil Lakhani](https://onco.cc/people/sunil-lakhani/), [Suzette Delaloge](https://onco.cc/people/suzette-delaloge/), [Tari A. King](https://onco.cc/people/tari-king/), [Thomas Bachelot](https://onco.cc/people/thomas-bachelot/), [Yeon Hee Park](https://onco.cc/people/park-yeon-hee/), [Yosef Yarden](https://onco.cc/people/yosef-yarden/)
- bottlenecks: [Biomarkers are not validated or standardised](https://onco.cc/bottlenecks/b-biomarker-validation/), [Knowledge reaches practice too slowly](https://onco.cc/bottlenecks/b-knowledge-diffusion/), [Most of the world has almost no cancer care](https://onco.cc/bottlenecks/b-global-access/), [Survivorship and late effects are neglected](https://onco.cc/bottlenecks/b-survivorship/), [The brain: barrier and sanctuary](https://onco.cc/bottlenecks/b-brain-delivery/), [Wrong doses](https://onco.cc/bottlenecks/b-dose-optimisation/)
- collections: [Living Beyond Breast Cancer](https://onco.cc/collections/src-lbbc/), [Susan G. Komen](https://onco.cc/collections/susan-g-komen/)
- biomarkers: [HER2 IHC 3+ (HER2-positive by immunohistochemistry)](https://onco.cc/biomarkers/her2-ihc-3-plus/), [HER2 ISH amplified (ERBB2 gene amplification)](https://onco.cc/biomarkers/her2-ish-amplified/)

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JSON: https://onco.cc/api/v1/entities/breast-her2-positive.json